In short, there appears to be a strong correlation between someone's feelings on same-sex marriage and their layman's interpretation of the law. These things are not the same. Right or wrong have only a passing flirtation with legal and illegal. They're never going to get married.
For example, here in Oregon, due to how poorly worded our computer crime laws are, if an ex-girlfriend tells me never to call her again and I call her a week later to tell her that she left some stuff at my house, I've committed a felony (it's a long story that I've researched thoroughly and I'm sure many of us can come up with equally absurd examples).
Did the Mayor of SF break the law? Whether or not he did has nothing to do with whether or not gay marriage is appropriate, though many people don't seem to be able to understand that there's a distinction here.
Here in Portland, Oregon, we have a slightly different situation. (Actually, we're talking about Multnomah county, but Portland is a name people know better.) Four of our five council members worked very hard to determine what the law was and they went out of their way to ensure that they stayed within the letter of the law -- though possibly not the spirit of it.
The result? There appears to be a strong correlation between someone's feelings on same-sex marriage and their layman's interpretation of the law. Surprise! There are many interesting arguments being thrown around and many of them are valid. However, few people seem to be able to decouple their feelings about gay marriage from an objective view of the law.